Athena Lamnisos, the chief executive of ovarian cancer charity The Eve Appeal, said: “The impact that this study could have on healthcare in the future for these cancers is promising and an exciting step forward in prevention.”

Samia al Qadhi, the chief executive of Breast Cancer Care, said the findings were fascinating, but there were still many questions to answer.

She said: “Being tested for a faulty gene is absolutely no walk in the park – preparing for possible life-changing results for a whole family is overwhelming and emotionally draining.

“Support for people tested and for the tough decisions that can follow must be at the heart of any plans for population screening.”

The UK’s National Screening Committee said it would look at the findings “with interest”.